carbs vs. fuel injection
12-07-2001 | 12:36 AM
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carbs vs. fuel injection
I would appreciate any advice concerning the performance advantages of an aftermarket Fuel injection system vs. a PMO setup.What system will make the most power? Who makes a good aftermarket injection kit for a 3.0SC?
12-07-2001 | 04:04 AM
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From: Africa
Morning,
Firstly it would be helpful to know what the application for the car is. Do you need a race engine (trackable), etc? Also if the car is to be classed you must check the relevant regs.
Secondly, if you're looking for sheer straight-line power then it would be cheaper to sell the SC and buy a turbo.
What year / engine number is your SC?
To the point
. Any engine works as a simple air pump. As long as you can push air through, it's easy to supply fuel. Unlike normal belief, the CIS on your car can handle plenty power (as in the 964 turbo 3.6), however your engine can't process enough air.
For any serious intake system, you need to get higher compression, higher valve lift, a better exhaust system and better ignition, etc. You can build a serious 3.0 engine, but often it's cheaper simply to increase / swop for bigger cc (just drop in a 3.6, tweak a little and Bob's your auntie
).
PMO's are carbs. Carbs are carbs! PMO's are good but unless your do as suggested above, you'll only get a few bhp on a standard cam SC. The fuel consumption will go up. Expensive choice unless you tweak the engine/exhaust.
You can fit EFI and map it for efficient and good fuel economy, however it's BIG $ on any engine. Again no significant bhp with the standard SC engine.
EFI on a race engine can make unbelievable power if set correctly. Motec, Halltec with TWM and similar will be far superior to any carb setup. It'll cost you plenty too though.
A few guys run cars with modified MFI. This setup can work very well, but yet again more cam and compression is needed for serious power.
The standard SC pistons do not allow for any wild cam, thus any modification needs to address this problem first. My suggestion is an engine transplant, it works out cheaper in the long run.
A good place to start / look is Bruce Andersons book. Best regards, enjoy your weekend. Tom.
Firstly it would be helpful to know what the application for the car is. Do you need a race engine (trackable), etc? Also if the car is to be classed you must check the relevant regs.
Secondly, if you're looking for sheer straight-line power then it would be cheaper to sell the SC and buy a turbo.
What year / engine number is your SC?
To the point
. Any engine works as a simple air pump. As long as you can push air through, it's easy to supply fuel. Unlike normal belief, the CIS on your car can handle plenty power (as in the 964 turbo 3.6), however your engine can't process enough air.For any serious intake system, you need to get higher compression, higher valve lift, a better exhaust system and better ignition, etc. You can build a serious 3.0 engine, but often it's cheaper simply to increase / swop for bigger cc (just drop in a 3.6, tweak a little and Bob's your auntie
).PMO's are carbs. Carbs are carbs! PMO's are good but unless your do as suggested above, you'll only get a few bhp on a standard cam SC. The fuel consumption will go up. Expensive choice unless you tweak the engine/exhaust.
You can fit EFI and map it for efficient and good fuel economy, however it's BIG $ on any engine. Again no significant bhp with the standard SC engine.
EFI on a race engine can make unbelievable power if set correctly. Motec, Halltec with TWM and similar will be far superior to any carb setup. It'll cost you plenty too though.
A few guys run cars with modified MFI. This setup can work very well, but yet again more cam and compression is needed for serious power.
The standard SC pistons do not allow for any wild cam, thus any modification needs to address this problem first. My suggestion is an engine transplant, it works out cheaper in the long run.
A good place to start / look is Bruce Andersons book. Best regards, enjoy your weekend. Tom.
12-08-2001 | 10:30 AM
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Since my 79 SC only has 80K original miles, I am reluctant to break it apart and do the piston and crank swap right now. Buying another motor has long term merit and is probably where I will go when I find the right deal. In the short run ,I have been considering a turbo setup that would work with the stock 8.5:1 piston set. If I could get in the 300hp territory without cracking the case I would be happy. It sounds as though an aftermarket EFI system would give me the most flexibility since I would primarily be driving this car on the street.
I do not have a computer on this car with only an air pump and cat to bog down the motor.This factored into my original thought about the PMO's. Is there a bolt on EFI sytem that would work well with the turbo setup? I might also consider a 98mm piston set. I will save the crank swap until I have more mileage. Thank you for any advice that you could offer.
I do not have a computer on this car with only an air pump and cat to bog down the motor.This factored into my original thought about the PMO's. Is there a bolt on EFI sytem that would work well with the turbo setup? I might also consider a 98mm piston set. I will save the crank swap until I have more mileage. Thank you for any advice that you could offer.
